Compact cold cathode indicator tube with thin ribbon vertical cathodes



s. KUCHINSKY 3,260,831 COMPACT COLD CATHODE INDICATOR TUBE WITH THIN RIBBON VERTICAL CATHODES Filed Sept. 18, 1961 July 12, 1966 INVENTOR. SAUL KUCH/NSKY Bx /ZMQ.

H N n m T A United States Patent 3,260,881 COMPACT COLD CATHODE INDICATOR TUBE WITH THIN RIBBON VERTICAL CATHODES Saul Kuchinsky, Somerville, N..'l., assignor to Burroughs Corporation, Detroit, Mich, a corporation of Michigan Filed Sept. 18, 1961, Ser. No. 138,793 25 Claims. (Cl. 313-1095) This invention relates to cold cathode gaseous indicator tubes.

At the present time, the most successful commercial cold cathode gaseous indicator tube is of the type shown in US. Patent No. 2,878,407. This type of tube includes a plurality of glow cathodes arranged in a stack in a gasfilled envelope. While this type of tube is eminently successful, the mechanical construction thereof, and particularly the stack arrangement of the cathodes, present certain problems. Thus, at the present time, there is a need for a cold cathode indicator tube in which a plurality of cathodes are provided, all of which are supported in simple fashion in the same stratum. The objects of the present invention are directed toward the provision of such a tube.

Briefly, a multiple cathode indicator tube embodying the invention includes a plurailty of cathode electrodes, all oriented in substantially the same stratum in the tube. The cathodes are ribbonor strip-like in construction and have minimum thickness but considerable width. The cathodes are each supported on one edge on a common support plate so that the opposite edge faces the viewing Window of the envelope and, when a cathode glows, its edge facing the viewing window appears to glow. With such a construction, the cathodes include portions which must cross each other, and, at the cross-over points, the cathodes are provided with mating notches which allow the required cross-overs while maintaining the cathodes electrically continuous but insulated from each other.

The invention is described in greater detail by reference to the drawing wherein:

FIG, 1 is a perspective view of a tube embodying the invention; and

FIG. 2 is a sectional view of the tube of FIG. 1.

A tube embodying the invention, referring to the drawing, includes an envelope 12 having a translucent viewing window 18 and a stem 22 which carries a plurality of tube pins 26, which extend into the envelope, and a conventional tubulation 30. Within the envelope an insulating support plate, for example, a mica disk 36, is positioned substantially parallel to the viewing window. The mica disk includes a top surface 37 and a bottom surface 38. In one suitable arrangement, the mica disk is seated on the pins 26 and carries a plurality of hollow eyelets 40, randomly arranged, which include a portion 44 secured to the disk and another portion 48 crimped or otherwise secured to a tube pin 26. A sufiicient number of such eyelets are provided to insure secure and rugged seating of the mica disk 36 on the pins.

The electrode assembly of the tube 10 ity of cathode electrodes 50 in the form of characters such as numerals, letters, or the like which are adapted to exhibit cathode glow, and the construction of the present invention allows the provision of a relatively large number of cathode electrodes. However, for purposes of illustraincludes a plural- 3,26%,881 Patented July 12, 1966 "ice tion, only two of such electrodes are shown. According to the invention, the cathode electrodes are made of thin strip material and are mounted on edge in the tube so that each cathode has an edge facing the viewing window of the envelope. The cathode electrodes are all mounted on the same insulating plate, and thus, are disposed in the same stratum in the envelope. Each cathode is of minimum thickness and is preferably of considerable width compared to the thickness.

Each cathode electrode 50 includes a top edge 54 and a bottom edge 58 and one or more notches extending downwardly from the top edge and upwardly from the bottom edge .to allow electrode cross-over. Thus, referring specifically to cathode numeral one, this electrode is provided with a first notch 62 extending upwardly from its bottom edge 58 and a second notch 64 extending downwardly from its top edge 54, the two notches being provided to accommodate portions of the cathode numeral seven which cross the numeral one. Similarly, the cathode numeral seven is provided with a notch 64' which extends upwardly from its bottom edge and a second notch 62 which extends downwardly from its top edge. The notches 62, 62' and 64, 64' are adapted to mate with each other to allow the electrode numerals one and seven to cross each other while maintaining insulation between them. It is clear that a sufficient number of notches is provided to accommodate the various other cathode electrodes contained in the envelope.

' Each of the cathode'electrodes is provided with a plurality of mounting tabs which are adapted to pass through apertures 74 in the mica disk 36. The tabs are adapted to be bent so that they bear against the lower surface 38 of the mica disk. A sufiicient number of tabs is provided to insure rugged and secure mounting of each cathode. In addition, at least one of the tabs associated with each cathode is of sufficient length so it can be electrically connected to one of the tube pins 26.

The tube 10 also includes an anode electrode which may be in any suitable form. In one suitable construction, the anode comprises a ring which surrounds the array of cathode electrodes 50. The anode, like the cathodes, may be secured in position by a plurality of tabs 84 which extend through suitable apertures 88 in the mica disk and bear against the lower surface thereof. At least one of the tabs 84 is secured to a tube pin 26. If desired, projecting arms 92 may be provided extending from selected regions of the anode ring toward the cathode electrodes to facilitate the initiation and maintenance of cathode glow.

In operation of tube 10, when a suitable operating potential is applied-between the anode 80 and one of the cathodes 50, the cathode exhibits cathode glow which is viewed along its narrow top edge facing the viewing winrow. Since the cathodes are very thin, preferably about three or four mils in thickness, the discontinuities formed by cross-overs are so small as not to be visible and each cathode provides continuous glow along its entire length.

The present invention thus provides a multiple cathode indicator tube which is compact, simple in construction, easy to assemble, and efficient in operation. The present invention has many advantages over the prior art and particularly the type of indicator tube wihch includes a stack of cathode electrodes. For example, the comparatively complex stack support construction and the comparatively high cost of assembly of a stack are avoided. The present invention also provides an easily assembled array of electrodes, all lying in a common stratum and viewable over a wide angle. In addition, the invention also provides a construction in which a comparatively large number of cathode electrodes of different forms may be provided, the cathode electrodes being ruggedly and securely mounted.

What is claimed is: 1. A cold cathode envelope filled with glow,

said envelope having a viewing window, and a plurality of uninsulated electrodes each adapted to exhibit cathode glow over its entire surface when energized with respect to an anode electrode, all of said electrodes lying in substantially the same stratum in said envelope, said electrodes comprising metal strip material and having greater width than thickness so that said electrodes have narrow edges, said electrodes being mounted on an edge and having the opposite edge facing said viewing window so that each electrode, when it glows, appears to glow along its edge facing said viewing window, said opposite edge being shaped to represent at least a portion of a character, all of said opposite edges lying in the same plane. 2. The tube defined in claim 1 wherein each electrode adapted gaseous glow tube comprising an a gas adapted to sustain cathode cross each other having mating notches at the cross-over points which allow the electrodes to be insulated from each other.

3. A cold cathode 4. The tube defined in claim 3 wherein said anode .comprises a metallic ring.

5. The tube defined in claim 3 wherein said anode comprises a metallic ring including a plurality of metallic projections extending toward said electrodes to facilitate the initiation and maintenance of cathode glow.

6. A cold cathode gaseous glow tube comprising an envelope filled with a gas adapted to sustain cathode glow,

said envelope having a viewing window,

an insulating disk disposed parallel to said window,

a plurality of electrodes each adapted to exhibit cathode glow,

all of said electrodes lying in substantially the same stratum in said envelope,

said electrodes comprising metallic strips having minimum thickness and having considerably greater width than thickness,

said electrodes having one of their thin edges supported on said disk, and mounting tabs secured to said elec trodes and extending through apertures in said disk and thereby securely engaging said disk,

gaseous glow tube comprising an a gas adapted to sustain cathode glow along said other edge; and mounting tabs secured to said electrodes and extrodes at the region of crossing notch in the edge of one electrode mates with the notch is not altered by their crossing.

10. The tube deztined in claim 6 wherein each electrode which is adapted to glow has top and bottom edges, the bottom edge being used for support and the top edge being used for viewing, some of said electrodes having notches extending downwardly from the top edge and ribbons having a length several times greater than its width and a Width several times shaped cathode glow contiguous a selected cathode electrode.

12. A cathode glow indicator tube as defined in claim 11 in which the anode is ring shaped and surrounds the conductive ribbons.

13. A cathode glow indicator .tube as defined in claim 11 in which the anode is ring shaped and surrounds the conductive ribbons and includes a plurality of radial projections extending inwardly toward said conductive ribbons.

14. A cathode glow indicator tube which utilizes the glow emission of excited gas molecules contiguous cathode 1 electrodes to produce recognizable characters comprising an envelope filled with a gas capable of sustaining a cathode glow andhaving a viewing window,

a plurality of cathode electrodes each formed of a conductive ribbon disposed within said envelope to have a viewing edge thereof facing said window,

each of said conductive ribbons having a length several times greater than its width and a width several times greater than its thickness,

each of said conductive ribbons also being shaped in the form of a substantially complete character to be viewed so that its edge facing the viewing window defines said character, the edges of the different conductive ribbons being in substantially the same plane, and

a plurality of conductive leads connected to said conductive ribbons and extending through said envelope for energizing one of said conductive ribbons to produce a character shaped cathode glow contiguous a selected one of said cathode electrodes.

15. A cathode glow indicator tube which utilizes the glow emission of excited gas molecules contiguous cathode electrodes to produce recognizable characters comprising an envelope filled with a gas capable of sustaining a cathode glow and having a viewing-window,

a plurality of cathode electrodes each formed of at least one uninsulated conductive ribbon disposed within said envelope to have an edge thereof facing said viewing window,

each of said ribbon conductors having a length substantially greater than its width and a width substantially greater than its thickness,

each of said conductive ribbons also being shaped such that its edge facing the viewing window defines at least a portion of a character to be exhibited,

and a plurality of conductive leads connected to said conductive ribbons and extending through said envelops for energizing at least one of said conductive ribbons to produce a cathode glow contiguous a selected one of said cathode electrodes,

16. A cathode glow indicator tube as defined in claim 15 in which the edges of all of the conductive ribbons facing the viewing window lie in substantially the same plane.

17. A cathode glow indicator tube as defined in claim 15 in which each of said conductive ribbons includes at least one tab extending therefrom for mounting said conductive ribbons within said envelope and for connection to one of said conductive leads.

18. A cathode glow indicator tube which utilizes the glow emission of excited gas molecules contiguous cathode electrodes to produce recognizable characters comprising an envelope filled with a gas capable of sustaining a cathode glow and having a viewing window,

a plurality of cathode electrodes each formed of an uninsulated conductive ribbon disposed within said envelope to have an edge thereof facing said viewing window,

each of said ribbon conductors having a length sub stantially greater than its width and a width substantially greater than its thickness,

each of said conductive ribbons also being shaped in the form of a character so that, when energized, its edge facing the viewing window defines a substantially continuous linear glow pattern in the shape of a character to be exhibited,

and a plurality of conductive leads connected to said conductive ribbons and extending through said envelope for energizing a selected one of said conductive ribbons to produce a cathode glow contiguous a selected one of said cathode electrodes.

19. A cathode glow indicator tube which utilizes the glow emission of excited gas molecules contiguous cathode electrodes to produce recognizable characters comprising an envelope filled with a gas capable of sustaining a cathode glow and having a viewing window,

a plurality of cathode electrodes each formed of at least one uninsulated conductive ribbon disposed within said envelope to have an edge thereof facing said window,

each of said ribbon conductors having a length substantially greater than its width and a width substantially greater than its thickness,

each of said conductive ribbons also being shaped such that its edge facing the viewing window defines at least a portion of a character to be displayed, the edges of the different conductive ribbons lying in substantially the same plane,

a plurality of conductive pins extending through said envelope for energizing one or more of said conductive ribbons to produce a cathode glow contiguous a selected one of said cathode electrodes, and

an insulated support plate mounted from at least one of said pins and containing tab receiving apertures therein,

each of the conductive ribbons having a plurality of tabs extending therefrom and through the apertures in said support plate for supporting the conductive ribbons, at least one such tab of each conductive ribbon being connected to a conductive pin to form an electrical connection to said ribbon.

20. A cathode glow indicator tube as defined in claim 19 in which each of the conductive ribbons has substantially parallel edges, one such edge facing the viewing window and the other abutting the support plate,

the tabs of the conductive ribbons extend from the edges thereof which abut the support plate,

and the tabs are deflected after passing through the support plate to support the conductive ribbons from said support plate.

21. A cathode glow indicator tube as defined in claim 19 in which the support plate is a disc formed of insulating material and in which said disc rests upon the conductive pins.

22. A cathode glow indicator tube which utilizes the glow emission of excited gas molecules contiguous cathode electrodes to produce recognizable characters comprising an envelope filled with a gas capable of sustaining a cathode glow and having a viewing window,

a plurality of cathode electrodes each formed of at least one uninsulated conductive ribbon disposed within said envelope to have an edge thereof facing said viewing window,

each of said ribbon conductors having a length substantially greater than its width and a width substantially greater than its thickness,

each of said conductive ribbons also being shaped such that its edge facing the viewing window defines at least a portion of a character to be exhibited,

at least two of said conductive ribbons crossing each other and having mating notches in their respective edges in the region of each such crossing, and

a plurality of conductive leads connected to said conductive ribbons and extending through said envelope for energizing at least one of said conductive ribbons to produce a cathode glow contiguous a selected one of said cathode electrodes.

23. A cathode glow indicator tube as defined in claim 22 in which each of said conductive ribbons includes at least one notch extending downwardly from one edge and at least a second notch extending upwardly from the other edge,

the respective notches of the conductive ribbons mating with each other in the region where said conductive ribbons cross whereby the conductive ribbons are maintained electrically isolated from each other,

the edges of the different conductive ribbons facing the viewing window lying in substantially the same plane.

24. A cathode glow indicator tube as defined in claim 22 in which each of the conductive ribbons includes tabs extending from one edge thereof, and an insulated support plate mounted within said envelope and containing apertures therein for receiving the tabs of the conductive ribbons for supporting said conductive ribbons from the support plate. 25. The tube defined in claim 1 wherein a plurality of said electrodes intersect each other in said stratum.

References Cited by the Examiner UNITED STATES PATENTS 2,618,697 11/1952 Metcalf 313l09.5 2,783,408 2/1957 Williams et a1 313109.5 DAVID J. GALVIN, Primary Examiner. GEORGE N. WESTBY, Examiner. C. R. CAMPBELL, Assistant Examiner. 

1. A COLD CATHODE GASEOUS GLOW TUBE COMPRISING AN ENVELOPE FILLED WITH A GAS ADAPTED TO SUSTAIN CATHODE GLOW, SAID ENVELOPE HAVING A VIEWING WINDOW, AND A PLURLITY OF UNINSULATED ELECTRODES EACH ADAPTED TO EXHIBIT CATHODE GLOW OVER ITS ENTIRE SURFACE WHEN ENERGIZED WITH RESPECT TO AN ANODE ELECTRODE, ALL OF SAID ELECTRODES LYING IN SUBSTANTIALLY THE SAME STRATUM IN SAID ENVELOPE, SAID ELECTRODES COMPRISING METAL STRIP MATERIAL AND 